Zach Zenner could see more action if he's the primary backup to Kerryon Johnson. Mark Konezny/USA TODAY Sports

The Lions have re-signed Zenner to a one-year deal, terms of which were not disclosed. Zenner has spent his entire career in Detroit.

What it means: Zenner probably will be the backup to Kerryon Johnson with perhaps an expanded role, as he showed his ability to be part of a rotation the final third of the 2018 season after Johnson suffered a knee injury that ended his season. Zenner rushed for 40 yards or more in each of his last four games, including a 21-carry, 93-yard game in the season finale against Green Bay, the most extended action he had seen since the 2016 season. The Lions know what they are getting from Zenner, a reliable player who will get the yards that are available to him. He won’t be a game-breaker, but he’s a consistent rusher who also offers special-teams value and is a good locker-room presence. Considering the Lions are likely to run the ball more, he could have more work than even his most productive year, an 88-carry, 334-yard, four touchdown campaign in 2016.

2019 Free Agency | Lions

What’s the risk: There isn’t a big one. Like many of Detroit’s other signings, the Lions know what they are getting in Zenner because he has been with them. He doesn’t offer the explosiveness of Johnson or the high-level pass-catching ability of Theo Riddick, but he can do everything well enough that you can plug him in during a pinch. That he might have a larger role this year as a short-yardage back or bigger back can only increase his value in the future. He might not have the upside of some of the other running backs on the market, but he’s a known commodity who at age 27 with only 174 NFL carries is not in as much danger of a downturn in his performance.

Trey Flowers should fit in well with former Patriots defensive coordinator and current Lions coach Matt Patricia. AP Photo/Mark Zaleski

The Detroit Lions agreed to terms with Flowers on a five-year deal expected to be between $16 million and $17 million per year, according to ESPN’s Adam Schefter. Here’s a closer look at the edge rusher who is coming from Matt Patricia’s old defense in New England.

What it means: Detroit needed a pass-rusher to replace Ezekiel Ansah and the franchise went out and nabbed the best one on the market. Flowers can line up in multiple spots in Patricia’s defense. This is, on paper, a massive signing for Detroit. He had 21 sacks in the first four years of his career -- all coming in the last three years when he became a starter. He’s an active player who can offer Patricia and defensive coordinator Paul Pasqualoni flexibility in how they run their defense. Paired with Romeo Okwara, DaShawn Hand, Damon Harrison and A’Shawn Robinson, the Lions now have a defensive line that is capable of both rushing the passer and stopping the run.

What’s the risk: The risk with a big-money contract -- and this is a massive-money deal -- is living up to the dollar amount. Flowers becomes Detroit’s highest-paid defender and now has to perform like it. While he’s put up good numbers, he has yet to have a double-digit sack season. At that money, it has to happen now.

Tight end Jesse James averaged 37 catches a year over the past three seasons with the Steelers. Charles LeClaire/USA TODAY Sports

The Lions are expected to sign James, agreeing to terms on an undisclosed deal according to ESPN’s Adam Schefter. Here’s a closer look at the tight end who is coming over from the Pittsburgh Steelers.

What it means: Both general manager Bob Quinn and coach Matt Patricia identified tight end as one of their biggest needs after last season's group underperformed. The Lions missed on every tight end target they had in free agency and the draft a year ago. Not so this time. The Lions are bringing in perhaps the best tight end on the market in James, a 6-foot-7 option who will be an immediate threat in the red zone for Matthew Stafford. The 24-year-old’s numbers won’t overwhelm you, but he did average 14.1 yards per reception last year, so he can stretch the field a bit. Signing James also lessens the need to take a tight end at No. 8 in the draft, something that has been rumored for the past few weeks. It could still happen, but James is a good enough player that he should be an upgrade.

What’s the risk: It’s unknown how James will fit in Darrell Bevell’s offense after playing four years in Pittsburgh. His yardage improved every year, but he has not caught more than 43 passes in a season and has never had more than three touchdowns in a year. He’s only had one season where he’s caught more than 75 percent of his targets (76.9 percent last year). There wasn’t a sure-fire star in this class like last year when multiple high-end tight ends were available, but he was among the best of what was around. And he also fills a true need.

Justin Coleman is another player familiar with how the Patriots operate defensively, playing under Matt Patricia when both were with New England. Scott W. Grau/Icon Sportswire

The Lions are expected to sign Coleman, who agreed to terms on a four-year deal for $36 million, according to multiple reports. Here’s a closer look at the cornerback who spent the past two seasons in Seattle after playing his first two years in New England.

What it means: The Lions are serious about playing primarily in a five defensive-back defense. The money reportedly being paid to Coleman will make him among the top slot corners in the game. Adding Coleman will solidify the inside of the Lions’ defense, giving them a player who has three career interceptions with two touchdowns. He’s played 52 games in his career and was a key piece for Seattle last season. It also provides more context to the release of last year’s starting outside corner, Nevin Lawson, who was a candidate to move inside this season before his departure. Plus, he’s another player familiar with how the Patriots operate, spending 2015 and 2016 in New England.

What’s the risk: Honestly not much -- even to how he’ll fit in with the rest of the defensive backs. Coleman is from the same hometown, Brunswick, Georgia, as Darius Slay and Tracy Walker. So communication should not be an issue at all. The risk now is more what happens on the outside opposite of Slay. That’s still the biggest hole in the secondary if you figure Walker slides into the open safety spot vacated by Glover Quin’s release. Detroit could still go after a safety here in free agency or the draft, but the Lions got a good piece here. Due to his time in New England, he should also understand the defense.

Danny Amendola had 59 catches for 575 yards in 15 games with the Dolphins last season. Tom DiPace/AP Photo

The Lions signed Amendola to a one-year deal with a base salary of $4.25 million with another $1.5 million that can be earned through bonuses and incentives. Here’s a closer look at the receiver who spent the past season with the Dolphins and five years before that with the Patriots.

What it means: Detroit needed to find a slot receiver after trading Golden Tate to Philadelphia last year. By signing Amendola, it shows the club had an idea on both the player and price range they were searching for all along. Amendola will turn 34 this year and is more of a complementary piece, as he has never had more than 700 yards in a season and more than 80 catches in a season since 2010. His value might be as much of an offensive Patriots culture ambassador -- think LeGarrette Blount last season -- as it is anything he’ll do on the field.

What’s the risk: General manager Bob Quinn and coach Matt Patricia wanted playmakers and Amendola isn’t one. At this point, he’s going to give you about 10 yards per reception and a catch percentage somewhere in the 70-80 percent range. He’ll be reliable, but he’s not going to change a game. He has been reasonably durable -- playing at least 12 games every year since 2013 -- but as a full-time starter last year, he didn’t do all that much (59 catches, 575 yards). He’s not the type of playmaker one envisioned.

The Lions are expected to sign offensive lineman Oday Aboushi to a one-year deal with undisclosed terms. Aboushi comes to the Lions from Arizona, where he played the 2018 season after being released by Oakland following training camp.

What it means: This seems like the Lions searching for someone to compete with Kenny Wiggins and Joe Dahl for the vacant right guard spot. Aboushi continually has had a job in the NFL, but often not on the same team for long. Since being drafted by the Jets in the fifth round in 2014, he has been with New York, Houston, Seattle, Oakland and Arizona. In 42 career games, he has started 32 of them – including eight in 2017 for the Seahawks during new Lions offensive coordinator Darrell Bevell’s final year with Seattle. With the Lions being on the hook for a $3.125 million cap hit for Wiggins, it could be interesting what happens with him both in the short and long term since none of Wiggins’ money is guaranteed for 2019. But, the Lions need someone to replace T.J. Lang.

What’s the risk: If the Lions are banking on either Wiggins or Aboushi to hold down the right guard spot, that could be a big weakness for Detroit. He graded out as the No. 41 guard by Pro Football Focus last year (considered average) and considering the value the Lions place on the offensive line it still feels like Detroit needs more on the interior. A draft pick could solidify things here. But Aboushi understands Bevell’s offense and is one of the few players the Lions have brought in who have worked under him.

Andrew Adams figures to compete for the No. 3 or No. 4 safety spot with the Lions. Jason Behnken/AP Photo

The Lions have signed Adams to a one-year deal with undisclosed terms. The Detroit Free Press first reported the signing. Adams comes to Detroit from Tampa Bay, where he spent one season after two years with the Giants.

What it means: Joke all you want about the Patriots Midwestern bureau in Detroit, but from a personnel standpoint, the Lions are enamored with players from the 2017 New York Giants defense. Adams is just the latest in that line from East Rutherford to Allen Park, following Devon Kennard, Damon Harrison and Romeo Okwara before him. Kelvin Sheppard, another former Giants linebacker, was on the Lions last year and is now a free agent. So there’s something coach Matt Patricia really liked from that defense. In Adams, Detroit gets a guy who can compete for the No. 3 or No. 4 safety spot with an outside shot at beating out both Tracy Walker and Tavon Wilson for the job.

What’s the risk: If the contract isn’t a large one, there’s little risk involved. He’s a playmaker -- four interceptions in just 355 snaps, although three came in one game against Carolina. He also broke up four passes. As long as Detroit isn’t counting on him to be a sure-fire starter (they aren’t -- or shouldn’t), it’s a smart depth signing. He also has some special teams value.

The Lions have signed wide receiver Tommylee Lewis on Tuesday from New Orleans. Other terms were not disclosed.

What it means: Lewis is an intriguing player for the Lions. His stats won’t blow you away, especially as a receiver with 20 career catches for 252 yards and two touchdowns in his three years with the Saints. But he’s primarily been a return specialist in his career, averaging 22 yards a kick return and 9.3 yards per punt return with New Orleans. Detroit has Jamal Agnew, the former All-Pro punt returner, but Lewis could end up challenging him or replacing him if the Lions believe Agnew will play a more significant role on defense. At worst, Lewis is a depth receiver signing who could be the kick returner. Lewis is best known for being the receiver on the pass interference non-call against Nickell Robey-Coleman that led to the Rams beating the Saints in the NFC Championship Game and eventually reaching the Super Bowl.

What’s the risk: Barring him signing an unexpectedly high contract, there’s little risk for Detroit in bringing in Lewis. Detroit hasn’t appeared inclined to re-sign TJ Jones so the franchise has been looking for a No. 4-5 receiver to compete with Andy Jones and Brandon Powell. The 5-foot-7 Lewis would likely be limited to slot work in the offense, doesn’t offer much position flexibility and it’s possible he doesn’t make the roster at all. But as long as there is minimal guaranteed money, it’s a reasonable second-wave signing for Detroit. Another benefit for the Lions with Lewis is he was college teammates with Lions receiver Kenny Golladay at Northern Illinois, so they know how to work well together.

The Lions are signing cornerback Rashaan Melvin to a one-year deal worth $3.5 million according to Adam Schefter. He played in Oakland last year.

What it means: It's another New England-familiar signing for the Lions. But in Melvin, Detroit gets a tall corner that Matt Patricia seems to favor. At 6-foot-2, Melvin could play opposite Darius Slay and be more of a physical presence for the Lions. It also gives Teez Tabor and Mike Ford real competition for the outside corner spot.

What's the risk: That Melvin is more DeShawn Shead than Rashean Mathis. The Lions signed Shead in hopes he would win the outside job opposite Slay last year and he ended up cut at the end of training camp. Unlike last year, Detroit doesn't have a safety blanket like Nevin Lawson to turn to since he signed with Oakland. If Melvin doesn't work, the Lions could be in a big hole early, having to rely on either Ford or Tabor, neither of whom is a proven entity in the NFL.